So f(x) = 0. Finding the zeroes of this purpose is the same as fixing this equation. During the paragraph just before, the zeroes of this function are +1 and −one, so They may be the answers of this equation. We got this equation by subtracting a similar point https://financefeeds.com/global-fx-market-summary-geopolitical-tensions-strait-of-hormuz-ecb-fed-23-june-2025/